Many conventional devices incorporate a motor for powering rotational components such as a fan or a pulley drive. The conventional motors may be single speed or two speed motors. The cost of the motor commonly is an important consideration in selecting an appropriate motor for a particular device or application. For example, a conventional two speed motor has two windings, and therefore, commonly is more expensive than a single speed motor. The added cost of the two speed motor may result in an increase in manufacturing costs associated with the device.
In many conventional devices, there is a need to monitor and control the speed of the motor, for example, to maintain a constant speed or to detect a failure or slowing of the motor below a predetermined or threshold speed. An integrated Hall effect sensor or device can be used to determine the speed of the motor by directly measuring the rotational speed of the motor. However, the added cost of the Hall effect sensor or device may further increase the manufacturing costs associated with the device.